Electric controlling means



W.' SCHWAGERMANN.

ELECTRIC cowmoume MEANS.

APPLICATION FILED APR. 25. 1916.

1,3 2,893, Patented Dec/21, 1920.

2 SHEETS-SHEET I- W. SCHWAGERMANN'.

ELECTRIC CONTROLLING MEANS.

APPLICATION FILED APR. 25, 19l6.

1,362,898, Patented Dec. 21,1920.

-2 SHEETS-SHEET 2.

UNITED STATES PATENT OFFICE.

WILLIAM SCHWAGERMANN. OF YONKERS. NEW YORKrASSI-GNOR TO WARD LEONARD ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

ELECTRIC CONTROLLING MEANS.

Specification of Letters Patent. t t e, 21, 1 20,

Application filed April 25, 1916. Serial No. 93.357.

To all whom it may concern:

e it known that I, lViLmAu Scmvaonn- )IANN, a citizen of the United States, residing at Yonkers, in the county of lVestchester and State of New York. have invented certain new and useful Improvements in Electric Controlling Means. of which the following is a full. clear, and exact specification.

The principal object of myinvention is to provide a new and improved device tor'controlling or regulating a storage battery system. Another object of my invention is to provide a regulator for an electric system such as is employed on motor cars for lighting, ignition. starting and other purposes. Still another object of my invention is to provide a regulator with means to prevent accidental discharging of the storage battery. These and other objects will be made apparent in connection with the following specification and claims, taken with the accompanying drawings, in which I have illustrabed one specific embodiment of my invention. It will be understood that the invention itself is defined in the appended claims.

Referring to the drawings, Figure 1 is a semi-diagrammatic view of the device;

Fig. 2 is a diagram showing the circuits more fullythan in Fig. 1;

Fig.3 is a face view of a vibratory contact;

and Fig. 5 is a diagram of a detail.

A direct current shunt wound generator with armature 2 and field windings 3 is driven by an automobile engine 1.- From the brushes of this generator, conductors lead to charge the storage battery 4.

A controlling magnet with the iron core 6 and iron pole pieces 7 .7 is provided with two windings, a shunt winding 8 and a series winding 9. At the respective ends of the magnet'are two armatures supported from the pole pieces at the opposite ends. Thus the pole piece 7 has a rigid attachment 10 carryin a flexible strip 11 of phosphor bronze, which supports the armature 12 in proximity to the pole piece 7 This armature 12 has a flat spring finger'14 carrying a contact 15 adapted to engage the fixed contact 17. Theleaf spring 18 tends to hold the armature 12' away from the pole piece 7 and it may be adjusted through the screw 20 supported by the frame extension 19.

Fig. 4 is a back view of another contact,

Another armature 22 is positioned oppositely to the one heretofore described. This has a flexible support 23 mounted at 24 on the pole piece 7 and the armature 22 extends in proximity to the pole piece 7. It carries a spring finger with two contacts 25 and 26 respectively adapted to engage the fixed contacts 30 and 31. These contacts are normally held closed by the spring 18'. which may be adjusted through the screw 20'.

On the core 6 are two coils, a series coil 9 and a shunt coil 8. The circuit of the generator 2 and battery 4 may be completed by the closing of the contacts 15 and 17: hence these contacts and the associated elements form a main circuit breaker. and it is to be noted that the series coil 9 is at the opposite end of the core 6 from the pole piece 7 adjacent to the armature 12. which controls the contacts 15 and 17. In circuit with the battery 4: are any desired translating devices such as incandescent electric lamps 32, electric horn ignition coils 34, starting motor 35, etc., all connected in parallel across the supply mains.

The shunt coil 8 is connected in shunt across the terminals of the generator 2, the circuit being repres nted in Fig. 2 as extending from the upper terminal of the generator to the end plates and core of the magnet, thence through the shunt coil 8 to the other terminal of the generator. The shunt field winding 3 of the generator is also connected in shunt across the generator terminals with a resistance 36 in series therewith,the circuit extending from the upper generator terminal to the magnet end pieces and core, then through the resistance 36 and field winding 3 to the other generator terminal. At 37 there is shown a branch extending to the fixed contact 30, and from the intermediate point 38 of the resistance 36 there is another branch to the fixed contact '31. As shown in Fig. 2, all of the resistance 36 is short-circuited, the circuit through the field winding 3 being traced as follows: 3730-- 25237'-6-7. When the armature 22 is attracted by the pole-piece 7, the contacts 25, 30 open ahead of the contacts 2631, so

that the portion of the resistance coil 36 to coil 36 to the right of the'poi'nt 38 is first shunted and then the entire resistance coil 36 is shunted.

Around the core 6 between the two coils 8 and 9 is an iron collar or flange 40, the function of which will be pointed out later.

Directing attention particularly to the armature 12 and associated parts, it will be seen that when the pole-piece 7 attracts this armature 12, the contacts 15 and 17 are brought together. The continuedmovement of the armature 12 toward the pole-piece 7 brings the bridge 16 to strike the leaf springl 14, which carries the contact point 15 an thus the contacts 15 and 17 are pressed firmly together. Between the time when the contact 15 initially touches the contact 17 and the time when the bridge 16 strikes the leaf spring 14, the intermediate movement'of the armature 12 causes a slight transverse rubbing of the contact 15 on the contact 17 so that the meeting surfaces are kept bright. When the pole piece 7' releases the armature 12, the contact 15 slides in the reverse direction across the contact 17 until the part 12' of the armature 12 strikes the leaf spring 14, whereupon the contacts 15 and 17 are very suddenlyseparated as if by a hammer blow. The leaf spring 28 tends to rest against the bridge 29 so that when the pole piece 7 attracts the armature 22, the bridge 29 strikes a hammer blow against the leaf spring 28, giving an abrupt separation of the contacts 26 and 31. There is the same sliding action between the contacts 25, 30 and between the contacts 26, 31 as heretofore described between the contacts 15, 17.

Assuming that the generator 2 is being driven by the engine 1 at a speed such as to cause the voltage generated thereby to approach or equal that of thestorage battery 4, the current through the shunt or voltage winding 8 will be sufficient to cause the armature 12 to be attracted and thereby close the contacts 15 and 17, and this will connect the charging generator through the series coil 9 to the circuit of the battery 4 and the translating devices 32, 33, 34 and At the time of closing the charging circuit, the excitation of the controlling magnet 6 by the shunt coil 8 is not sufiicient to attract the armature 22 and therefore the resistance 36 is short-circuited, giving a strong field excitation of the generator. W'ith this strong field, an increase of speed of the engine 1 gives a substantial increase in the charging current passing from the generator to. the battery through the series coil 9. The magnetomotive force of this coil 9 being addictive to that of the voltage coil 8, the attraction of the armature 22 increases until it is drawn to the pole-piece 7 thus placing the resistance 36 m series with the field winding 3, in two successive steps as heretofore indicated. The insertion of this resistance 36 in series with the field winding 3 cuts down the filed strength and thereby reduces the current output of the generator through the coil 9 so that its effect is insufficient to hold the armature 22 to the pole piece 7 against the force of the spring 1.8. Accordingly, the armature 22 falls back and cuts out the resistance 36 in two steps as already described and the field 3 strengthens and the flow of current through the coil 9 again increases in consequence. Thereupon the same cycle of steps is repeated again and again in rapid succession. The armature 22 is given a vibratory movement which causes a fluctuating current to flow from the dynamo armature.

The short-circuiting or cutting out of the resistance 36 causes the current in the series coil 9 to rise rapidly until the resistance controlling contacts 25, 30 and 26, 31 are separated. This is due to the proportion of the field winding 3 and resistance 36, and also due to the fact that the ohmic resistance in the circuit including the generator armature and the battery is extremely low, a comparatively small. increase in the voltage of the generator making a large change in current through the battery 4: and series coil 9. But even a large change in the current through the battery 4 does not materially affect the voltage across its terminals, because the internal resistance of the battery is so low that the increase of potential drop due to the current passing through the low battery resistance is very low compared with the normal counter volts of the battery, and the counter volts in the battery are substantiall, independent of the current through the battery It will be understood that the armature 12 serves as an automatic protective switch insuring that the generator will be connected in circuit with the battery only when the generator voltage is sufficiently high, and that if from any cause the generator voltage becomes abnormally reduced the reone and the same core 6 to actuate both the circuit breaker with the contacts 15, 17 and the vibratory armature 22. It is desirable to have the effect of the series coil 9 upon the vibrator 22 much greater than the effect of the shunt coil 8, so that a slight change in the current output of the generator will 130 the vibrator 22. lVith these proportions, if,

the engine is standing, it will ordinarily have died down to that condition gradually enough so that'the contacts 15, 17 will have opened at an intermediate stage as heretofore described. But, if while the engine is standing, these contacts are pressed together by hand, or if they become closed in any other way, they will complete the low resistance circuit through the battery 4 and generator armature 2 so that the battery current will flow in a reverse direction through the armature 2. Under these circumstances the ampere turns of the series coil 9 will be opposed-to those of the shunt coil 8, but the eifect of the series coil 9 will so greatly exceed that of the shunt coil 8 that the coil 9 might have a tendency to hold the armature 12 and thus permit the battery 4 to run down, which would be bad enough even if the excessive current through the armature 2 did not burn the latter out.

By placing the iron collar or flange 40 between the series coil 9 and the shunt coil 8 upon the core 6, and by putting the series coil 9 at the opposite end of the core 6 from the armature 12 of the circuit breaker, this difliculty is obviated. With this arrangement, when the engine is standing still, even if the contacts 15, 17, are closed manually, the resultant magnetic attraction by the end of the core 6 upon the armature 12 will not be sufficient to hold the contacts '15, 17

closed. As has already been stated, under these circumstances the magneto motive forces produced in the core 6 by the two coils 9 and 8 will be opposite to each other; in so far as these magnetomotive forces are equal and opposite they will tend to form substantially equal like poles at the ends of the core 6 and an intermediate opposite pole at the periphery of the flange 40. The increased magnetomotive force due to the greater number of ampere turns of the coil 9. creates an additional magnetomotive force which extends largely through the circuit indicated by the dotted lines 41 in Fig. 5 and in so far as this additional flux threading through the coil 9 emerges at the pole piece 7', it is not enough completely to overcome the opposing magnetomotive force of the shunt coil 8 and produce an effective attraction on the armature 12. 7

Accordingly, with the engine standing still, if the contacts 15, 17 should be closed manually or otherwise, thus permitting the battery current to flow in reversed direction through the series coil 9 and the generator armature 2, the resultant attraction of the core 6 on the armature 12 would be insufficient to hold the contacts 15, 17 closed in the absence of an abnormal and external force to hold them closed as just suggested.

Having thus described my invention, what I declare as new and desire to secure by Letters Patent of the United States is 1. In combination, a direct current generator, a storage battery to be charged thereby, a permeable core with a collar of like character around it and with a series coil and a shunt coil on respective sides of said collar, armatures at the respective ends of the core, a switch in series with the series coil controlled by the armature at the opposite end of the core from said series coil, and means to regulate the field of the generator controlled by the armature at the end of the core opposite the shunt coil.

2. In combination, a direct current generator, a storage battery to be charged thereby, and an electric regulator comprising a core with two coils thereon, armatures at the respective ends of the core, and means between the coils to facilitate the leakage between the coils of a flux through one of said coils.

3. In combination, a direct current generator, a storage battery to be charged thereby, and an electric regulator comprising two coils on a common core, said core having a branch of permeable material between the two coils, whereby a flux generated in the core by one coil may pass through said branch and complete its path without threading through the other part of the 105 core.

4. In combination, a direct current generator, a storage battery to be charged thereby, a series coil, a shunt coil, a common core for said coils, a circuit breaker associated 110 with the end of the core remote from the series coil, a regulator associated with the other end of said core, and means between the two coils to facilitate the leakage of magnetic flux from the core between said coils. 11

5. In combination, a direct current generator, a storage battery to be charged thereby, and an electric regulator comprising a core with two coils thereon, two armatures each pivoted near a respective end of the 12 core and each with a variable air gap near the other end thereof, two coils on said core and a branch path of permeable material between said coils, whereby a magnetic flux generated in the core by one coil can com- 125 plete its circuit without threading through the other coil.

6. In combination, a direct current generator, a storage battery to be charged thereby, a series coil, a shunt coil, a common core 130 for said coils, two armatures each pivoted near a respective end of said core and with a variable air gap at the opposite end thereof, series contacts controlled by the armature whose air gap is remote from the series coil and a branch path of permeable material on the core between the coils whereby a magnetic flux generated in the core by the series coil may complete its circuit without traversing the air gap for the armature that controls the series contacts.

7. In combination, a direct current generator, a storage battery to be charged thereby and a regulator, said regulator comprising two tandem coils on a common core, wound additively for production of flux under charging conditions, but oppositely under the condition of discharge from the battery through the generator, and means between said coils to facilitate the leakage of flux at that point under such condition of discharge.

8. In combination, a direct current generator, a storage battery to be charged thereby and a regulator, said regulator compris ing a series coil and a'shunt coil in tandem on a common core, the ampere turns of the menace seriescoilbeinggreaterthan of the shunt coil and both wound additively for production of flux under charging conditions, a cut-out associated with the end of the core remote from said series coil and means between said coils to facilitate the leakage of flux at that point under conditions of opposite flux production thereby.

9. In combination, a direct current generator, a storage battery to be charged there by and a regulator, said regulator comprising two coils on a common core wound additively for production of flux under charging conditions, but oppositely under the condition of discharge from the battery through the generator, a cut-out within the influence of the magnetism additively produced in said core and means to facilitate leakage of flux from said core past said cut-out under conditions of opposite flux production by said coils.

In testimony whereof I afiiX my signature in presence of two witnesses.

WILLIAM SCHWAGERMANN. Witnesses:

LEONARD Knnnnn, ALFRED E. WALLER, 

